244 I. I. Krolenko 



deposits, covered with shallow alluvia. The value of the anisotropy coefficient 

 of such deposits varied between 1.2 and 2.5. The electrical homogeneity 

 over the area is established by parametric profiles of resistances with spacings 

 equal to the length of the AB line adopted for working with the loop method 

 in the given region. The loop method can also be used to determine the 

 direction of dip of the reflecting highly -resistant horizon, covered with 

 electrically homogeneous rocks. The accuracy of the results of surveying 

 by the loop method is also ensured by the accurately defined forms of the 

 buried fold (angle of dip of the studied rocks from 8 to 80°) and the gentle 

 relief of the surface. 



The presence of these favourable conditions on the areas of the Kerch 

 peninsula determined the possibility of extensive work with the loop method 

 and the effectiveness of the results. 



The first investigation was carried out in 1937 at the Priozernoe (Chonge- 

 lekskoe) petroleum deposits and then at the Pogranichnaia* (Chorelekskaia) 

 and Malo-Babchikskaia anticlines for determining the tectonic structure 

 of these areas. This work showed the position of the axes of the structures and 

 marked the regions of greatest amplitude. At the Priozernyi deposit the 

 loop method combined with electrical profiling (mapping the strip of the 

 Middle Sarmatian limestone on the flanks of the structure) revealed a number 

 of cross-cutting disturbances. 



The nature of the relationship between the Chorelekskoe and Opukskoe 

 upfolds and the Malaia Babchikskaia structure with the Katerlezskii 

 dome<^^'^*). In 1950, this work extended the knowledge of the 

 Chongeleksko-Chorelekskaia antichnal zone. This zone, in the limits of 

 the Kerch peninsula, according to the data of the loop method begins at 

 the south-west of the Koyashskoe lake in two small anticlines — Chokur- 

 Koyashskaia and Opukskaia, separated by a small saddle, and ends at the 

 north-east of the Zaozernaia (Tobechikskaia) fold, a considerable part of 

 which is under the water of the Kerch Straits (Fig. 2). 



Significant corrections were introduced on the basis of the work carried 

 out by the loop method and core drilling in 1950 in the zone of the Malaia 

 Babchikskaya structure, which was coordinated with the deposition of 

 petroleum. As well as the data on this fold and the Katerlezskii dome adjoining 

 it from the south-west, to the south of the Malaia Babchikskaya anticline 

 was mapped the Yuzhno-Babchikskaia fold with a very narrow closure, 

 bent in the form of a crescent (^^' "^K In between the three upfolds there 



* In order to avoid errors the Russian adjectival form is used for the structures imless 

 ithe correct place name is well known. [Editor's footnote]. 



